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Recall of eight childhood communicable diseases and other illnesses was validated among 95 adults by comparison to longitudinal childhood health records. Self-reports at age 50 of several illnesses were highly accurate; however, German measles was correctly recalled by only 34% of subjects. Similar levels of accuracy were consistently found among a subset who also completed health history interviews 8 and 20 years earlier. Over-reporting of some health events was common. Past exposure to viral or bacterial agents is sometimes assessed in case-control studies by self-reports. Misclassification of prior exposure due to faulty recall may distort true associations between childhood illness and chronic disease in later life. 相似文献
5.
Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
6.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
7.
Autoradiographic localization of kappa opiate receptors in CNS taste and feeding areas 总被引:1,自引:0,他引:1
Recent evidence suggests that kappa opiate receptors may play a key role in the regulation of appetite. Such evidence implies that kappa receptors might be localized within specific brain areas known to regulate ingestive behaviors. On the basis of this implication we employed an in vitro film autoradiographic technique using 3H-ethylketocyclazozine as ligand to identify putative kappa receptors within CNS "taste" nuclei and surrounding areas. Coronal cryostat sections of rat brain were incubated with ligand in the presence of D-Ala2, D-Leu5-enkephalin (DADLE) and morphine, apposed to LKB Ultrofilm for 60 days, processed and kappa receptor densities evaluated with the aid of a hand held photometer and video image analyzer. Highest kappa receptor densities were found within various gustatory and feeding sites including the rostral pole of the nucleus of the solitary tract, parabrachial nuclei, ventral posterior and medial portions of the thalamus, medial hypothalamus, medial nuclei of the amygdala and bed nucleus of the stria terminalis. Various other midline and medial limbic areas also showed significant kappa densities. 相似文献
8.
G E Laramore J M Krall F J Thomas T W Griffin M H Maor F R Hendrickson 《International journal of radiation oncology, biology, physics》1985,11(9):1621-1627
Between June 1977 and April 1983, the Radiation Therapy Oncology Group (RTOG) sponsored a Phase III randomized study investigating fast neutron radiation therapy in the treatment of patients with locally advanced (Stage C and D1) adenocarcinoma of the prostate gland. Patients were randomized to receive either conventional photon radiation therapy or fast neutron irradiation used in a mixed-beam treatment schedule (neutron/photon). A total of 91 analyzable patients were entered in the study; 78 of them were treated without major protocol deviations. The two treatment groups were balanced in regard to all major prognostic variables. Actuarial curves for "overall" survival, "determinantal" survival and local/regional control are presented both for the entire group of 91 patients and the 78 patients treated within protocol guidelines. The overall local/regional tumor recurrence rate is 7% for the mixed-beam treated group of patients and is 22% for the photon (X ray) treated group of patients. The difference is statistically significant at the p = 0.05 level. For the entire group of 91 evaluable patients, the 5-year "overall" survival rate is 62% for the mixed-beam-treated group and 35% for the photon-treated group. This difference is also statistically significant (p less than 0.05). However, this statistical significance is lost when the smaller number of patients treated strictly within protocol guidelines is considered. The significance is regained (p less than 0.02) when one looks at "determinantal" survival, which uses active cancer at time of death as the failure endpoint. This study demonstrates that a regional treatment modality, in this case mixed-beam irradiation, can influence both local/regional tumor control and survival in patients with locally-advanced adenocarcinoma of the prostate gland. 相似文献
9.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy. 相似文献
10.
Sztajzel J Périat M Marti V Krall P Rutishauser W 《The Journal of sports medicine and physical fitness》2000,40(3):233-239
BACKGROUND: The purpose of this study was to investigate the effect of sexual activity on cycle ergometer stress test parameters, on plasmatic testosterone levels and on concentration capacity in high-level male athletes. METHODS: Experimental design. Analysis of two days of testing accomplished in a laboratory setting, comparing a day with to a day without sexual activity (control day). Participants. Fifteen high-level male athletes, consisting of 8 team players, 5 endurance athletes and 2 weight-lifters, participated in the study. Measures. Each subject completed the following on each test day: two maximal graded stress tests on a cycle ergometer and a one-hour exercise stress test coupled to an arithmetic mental concentration test. Blood samples of testosterone were obtained and cardiac activity of each athlete was monitored with a 24-hour ECG tape recording over the two test days. RESULTS: Significantly higher differences were achieved for post-effort heart rate (HR) values at 5 minutes (p<0.01) and at 10 minutes (p<0.01) during the recovery phase of the morning stress test 2 hours after sexual activity. These differences disappeared during the recovery phase of the afternoon stress test performed approximately 10 hours after sexual intercourse took place. CONCLUSIONS: Our findings show that sexual activity had no detrimental influence on the maximal workload achieved and on the athletes' mental concentration. However, the higher posteffort HR values after the maximal stress test on the morning of sexual intercourse suggest that the recovery capacity of an athlete could be affected if he had sexual intercourse approximately 2 hours before a competition event. 相似文献